The invention relates to a device for drying substrate disks by irradiation with ultraviolet light, wherein during the irradiation process a glass plate rests on the substrate disk.
Such drying devices are especially employed for the manufacture of compact disks or CDs, mini-disks, magneto-optical disks, CD-ROMs, CD-Rs, photo-CDs and/or video disks, and/or digital video disks (DVDs). Especially for the manufacture of substrate disks which are comprised of two partial substrates to be glued together, the glass plates are placed during the drying process onto the substrate disks in order to prevent that the substrate during the drying process will buckle or lose its planar shape. The term drying is to include also the curing of adhesives with which, for example, two substrates are glued to form a substrate disk. The substrate disks to be dried are conventionally positioned on a turntable which rotates in a cycled manner and transports the substrate disks into the drying area of the drying device. Before the substrate disks enter the drying area, the glass plates are placed by a glass plate handling device onto the substrate disks and are removed therefrom after the drying process when the substrate disks have been rotated out of the drying device. By placing the glass plates onto the substrate disks with the aid of a glass plate handling device, it cannot be prevented that non-uniform pressure is applied to the substrate disks. This changes the layer of adhesive positioned between the substrates to be glued which can be changed by pressure in the not yet dried or not yet cured state with respect to its layer thickness. It was found that this causes high reject rates and also considerably impairs the quality of the finished substrate disks.